JP4724581B2 - Surface-treated metal material with excellent magnetic properties and method for producing the same - Google Patents

Description

  The present invention relates to a metal material having high magnetic iron-based alloy plating on the surface and excellent magnetic properties, and a method for producing the same.

  Silicon in steel has excellent properties such as increasing the strength of steel plates, and is therefore beneficially used as an additive element in steel materials. Among them, in particular, high silicon-containing steel sheets are widely used as electromagnetic materials for motors and transformers because of their excellent electromagnetic characteristics. The addition of silicon has the effect of increasing the electrical resistance of the steel and reducing the total iron loss. Therefore, iron loss is reduced as the silicon content of high-silicon steel increases, and magnetostriction is zero when the silicon content is 6.5%, the maximum permeability is peak, and it has traditionally shown ideal electromagnetic characteristics. Are known.

  At present, high silicon-containing steel sheets are mainly produced by a rolling method, but due to poor workability, only about 3.5% silicon is produced. This is because cracks occur during processing during rolling, and production is difficult. In order to overcome this, a method such as devising various rolling methods has been proposed in order to improve the characteristics without increasing the Si component ratio (Patent Document 1). On the other hand, various methods in place of the rolling method have been proposed. For example, a method of producing a high silicon-containing steel sheet by chemical vapor deposition in silicon tetrachloride gas and heat diffusion is proposed (Patent Documents 2 and 3). With this method, there is no worry of cracking during rolling. In addition, a method for producing a steel plate having excellent electromagnetic properties by performing Al or Al-Mn plating by a hot dipping method or a molten salt electrolysis method instead of a vapor deposition method has been proposed (Patent Documents 3 and 4). This method has no cracking during processing, and the film growth rate is fast, so it can be said that this method is economically excellent.

JP 2005-256019 JP-A-62-227032 JP-A-62-227033 JP-A-7-258863 Japanese Patent No. 2827890 Electroplating Study Group, Plating Textbook, 137 pages, Nikkan Kogyo Shimbun (Showa 61)

  However, for example, the method of Patent Document 1 is not an essential solution and is not economical. In addition, the methods of Patent Documents 2 and 3 are generally not considered to be economical methods, although the film growth rate is generally slow and not industrially impossible. The method of applying Al or Al-Mn plating by the hot dipping method or the molten salt electrolysis method of Patent Documents 3 and 4 has a limit as an alternative method compared to the characteristics of silicon steel plate, compared with 6.5% Si steel I must say it is inferior. It is conceivable to apply this method to silicon. However, if silicon is to be plated by the hot dipping method, the plating bath temperature must be higher than that of Al. It is intense and not a practical method.

  In view of the above problems, the present invention seeks to provide a surface-treated metal material having excellent magnetic properties by an economical manufacturing method that does not require a special high temperature and has a high film formation rate.

  The inventors of the present invention have made various studies on the manufacturing technology of a metal material having a high Si concentration regardless of an alternative element. As described above, silicon is an element having a high melting point, high oxidizability, and impossibility of electroplating from a normal aqueous solution.

  In order to solve the above-mentioned problems, the present inventors have intensively studied, and as a result, have arrived at the inventions having the following (1) to (7). This is because it has been found that a metal material exhibiting excellent magnetic properties can be obtained by forming an iron-based plating in which metal fine particles mainly composed of silicon are dispersed on a metal material.

That is,
(1) In an aqueous solution containing at least one of Fe ²⁺ , Ni ²⁺ , and Co ²⁺ ions, one or more of Fe, Al, and Mn as selective elements in addition to Si and unavoidable impurities in Si as a main component At least part of the surface of the metal material, and an iron-based plating layer in which the Si particles are dispersed is formed by electroplating on at least a part of the surface of the metal material. a part of the surface, a surface treated metal material having a Si-containing iron-based plating layer, the front surface process you wherein the Si content of the plating layer is not more than 3.5 mass percent 10 wt% Metal material.
(2) The surface-treated metal material according to (1), wherein the surface-treated metal material is subjected to a heat diffusion treatment at a temperature of 1000 ° C. to 1200 ° C. after the electroplating.
(3) the plating layer, by mass%, Al: 2.0 percent 8.0% or less, Mn: according to, characterized in that it comprises at least one 0.5 percent 1.5% or less (1) or (2) Table surface-treated metal material.
(4) the thickness of the plating layer is 1μm or more 100μm or less (1) front surface treated metal material according to any one of the - (3).
(5) The composition of the metal material is, by mass%, C: 0.001% to 0.010%, Si: 0.01% to 3.5%, Mn: 1.5% or less, Al: 0.001% to 3.0%, and the balance There is a Fe and unavoidable impurities (1) front surface treated metal material according to any one of the - (4).
(6) Using a plating bath in which fine particles containing Si as a main component are suspended in an aqueous solution containing at least one kind of Fe ²⁺ , Ni ²⁺ , and Co ²⁺ ions, An iron-based plating layer in which Si fine particles are dispersed is formed on the surface by electroplating, and the fine particles mainly composed of Si include only one or more of Fe, Al, and Mn as selective elements in addition to Si and inevitable impurities. The manufacturing method of the surface treatment metal material excellent in the magnetic characteristic characterized by being able to contain .
(7) The method for producing a surface-treated metal material according to (6), wherein after the electroplating, a heat diffusion treatment is further performed at a temperature of 1000 ° C. or higher and 1200 ° C. or lower.

  ADVANTAGE OF THE INVENTION According to this invention, the metal material excellent in the magnetic characteristic can be provided efficiently irrespective of a rolling method or a vapor deposition method.

  Details of the present invention will be described below.

  The iron-based plating layer described in the present invention is a plating containing 50% or more by mass% of any one or more of iron, nickel, and cobalt, and hereinafter referred to as iron-based plating. When used as an electromagnetic steel sheet, iron, nickel, and cobalt are elements having excellent electromagnetic characteristics. Although these alloys may be used, it is necessary to contain a total of 50% by mass or more of these three types of elements in order to effectively produce magnetic properties.

  Next, the fine particles mainly composed of silicon used in the present invention will be described. These fine particles are fine particles composed of elements that inevitably have oxides and the like present on the surface but otherwise do not form a compound with oxygen, nitrogen, or the like. This element is mainly composed of silicon in the present invention. In the present invention, it is essential that the fine particles contain silicon as a main component, but it is more effective that the fine particles contain an element effective for magnetic properties, for example, Fe, Al, Mn and the like.

  Al is an element effective for magnetic properties, but it deteriorates rolling workability like Si, so that it is effective to be present in the plating layer in the present invention. In addition, like Si and Al, Mg is an element that is difficult to electroplate from an aqueous solution, and it is effective to contain Mg in the metal fine particles because it is present in the plating layer. Also, for the purpose of facilitating heat diffusion, an alloy with Fe or Al is preferable.

  “Containing silicon as a main component” means that silicon has the maximum content among constituent elements in fine particles, and preferably 50% by mass or more.

  Such fine particles are dispersed in the plating layer, and the amount of the dispersion should be in the range of more than 3.5% to 10% by mass in terms of Si in the plating layer. Magnetic properties, especially iron loss, are minimized when the silicon content in steel is 6.5%, but then turn up, and if it exceeds 10%, is it the same as the iron loss when the Si content is 3.5%? Since it becomes inferior, it is meaningless to add more than 10%. When the silicon content is 3.5% or less, the production by the rolling method is easy, and the effect of the present invention does not appear.

  In addition, the presence of Al or Mn simultaneously with Si in the plating layer can increase the electric resistance and further improve the magnetic properties. The amount is preferably 2.0% to 7.0% by mass% of Al. If it is 2.0% or less, it can be produced by a rolling method like Si, and the effect of the present invention does not appear. If it exceeds 7.0%, the effect is saturated, so this is the upper limit. When the amount of Mn added is 0.5% or less, almost no effect appears. Also, if it exceeds 1.5%, the effect will be saturated, so over 0.5% and 1.5% or less.

  The plating thickness is preferably in the range of 1 μm to 100 μm. In order to show magnetic characteristics, the effect is often not expected when the plating thickness is less than 1 μm. Further, the effect is saturated at a thickness of more than 100 μm in a high frequency range of 1 kHz or higher where high Si-containing steel exhibits excellent electromagnetic characteristics.

  Quantification of silicon present during plating can be confirmed by methods such as fluorescent X-rays. When silicon is significantly contained in the steel sheet, the presence of silicon can be quantified by EPMA analysis of a cross section or the like. By comparing the distribution of silicon and oxygen or nitrogen, it is also possible to identify whether the compound is not a compound such as silicon or silicon oxide. Moreover, it is easy to identify whether it exists in the plating or in the steel sheet because of the difference in structure between the rolled steel sheet and the Fe plating.

  Such iron plating in which fine particles mainly containing silicon are dispersed is present on at least a part of the surface of the metal material, thereby improving the magnetic characteristics.

  It is more desirable to further subject the plating layer to heat diffusion treatment in order to further improve the uniformity of the plating layer. This heat treatment is suitably performed in an inert or reducing atmosphere in order not to form an oxide layer on the surface. If the heating temperature is 1000 ° C. or higher, diffusion can proceed efficiently. The higher the temperature, the faster the diffusion, but the upper limit is 1200 ° C due to economy and versatility.

  The metal material used as the base material may be a metal such as steel, aluminum, or copper, but the composition is particularly mass%, C: 0.001% to 0.010%, Si: 0.01% to 3.5%, Al: 0.001 If it is a steel material that is not less than 3.0% and not more than 3.0% and Mn: not more than 1.5% and the balance is Fe and inevitable impurities, it can be expected to show better magnetic properties.

  C is an element effective for improving the strength of the steel sheet, and is preferably added in an amount of 0.001% or more. However, if it exceeds 0.01%, the iron loss is adversely affected.

  Since Si increases electric resistance and is effective for magnetic properties, addition of 0.1% or more is desirable. However, if it exceeds 3.5%, workability is inferior.

  Al is also an element effective for magnetic properties like Si, and is preferably added in an amount of 0.001% or more. However, since it shows an adverse effect when steel is cast or rolled, the upper limit is made 3.0%.

  Mn is also effective for increasing the electrical resistance like Si and Al, but the upper limit was set to 1.5% from the viewpoint of economy.

  The method for forming the iron-based plating layer applied to the metal material is preferably formed by electroplating. The plating bath component in the case of iron plating may be an ordinary method using iron sulfate or iron chloride as described in Non-Patent Document 1, for example. Depending on the purpose, an alloy plating bath of elements other than iron, nickel and cobalt, for example, zinc and iron can be used. Zinc can be expected to contribute to corrosion resistance and the like. However, since zinc has a low boiling point, it is required to be careful of temperature when accompanied by heat diffusion.

  The method for producing fine particles is not particularly defined. A method of pulverizing and classifying silicon or a silicon alloy ingot is economical and general. Since the size of the fine particles is present during plating, it is necessary to be smaller than the plating film thickness. Smaller sizes are more effective for exhibiting magnetic properties, and it is appropriate that powder with a diameter of 5 μm or less accounts for 50% or more (average particle size is about 5 μm) from the efficiency of incorporation into plating. is there. More desirably, the powder having a diameter of 1 μm or less accounts for 50% or more.

  The fine particles containing silicon as a main component are suspended in a plating solution to obtain a plating solution. The amount of fine particles to be suspended is not strictly defined, but if it is too small, the required amount cannot be taken in, the plating efficiency will be reduced, and if it exceeds a certain level, it will not be effective and it will not be economically appropriate, so it will not be economically appropriate. 5 g or more and 50 g or less. In order to efficiently incorporate the powder into the plating film, it is preferable to add a surfactant to the plating solution. However, excessive addition of a surfactant may cause problems such as a decrease in the efficiency of the plating itself and deterioration of surface properties in the case of a plating solution with a high iron ratio. Desirably 0.01 g or more and 5 g or less per liter.

  A method of electroplating a metal material using a plating solution as described above may be a conventional electroplating method.

  In addition to the above-described electroplating from an aqueous solution, a low melting point molten salt electrolysis method using a non-aqueous solvent is also effective as a method for forming an iron-based plating layer containing Si.

  After forming a metal plating containing Si by electroplating, heat diffusion treatment can be performed, for example, in a continuous line, such as heating in an alloying furnace, or batch annealing in which each coil after plating is heated. I do not care. The cooling rate is not specified. An arbitrary cooling rate can be selected depending on required properties such as strength and workability.

  The surface-treated metal material thus manufactured can then be subjected to well-known post-treatments such as chemical conversion treatment and formation of an insulating film.

  The surface-treated metal material of the present invention can be used for a motor or the like as a material having characteristics equivalent to or surpassing that of a non-oriented electrical steel sheet.

(Example 1)
By using a cold rolled steel sheet with a thickness of 0.1 mm, which includes C: 0.015%, Si: 0.05%, Mn: 0.2%, Al: 0.03%, the balance being Fe and unavoidable impurities. After degreasing and pickling, Si fine particle-dispersed Fe plating was applied to the surface of the cold-rolled steel sheet by electroplating under the following plating conditions.
<Plating conditions>
Anode: SS400
Bath composition: FeSO ₄・ 7H ₂ O 250g / L FeCl ₂・ 4H ₂ O 35g / L NH ₄ Cl 20g / L
(pH adjusted to 3.0-3.5) Surfactant (Daiichi Pharmaceutical Co., Ltd .; Charol DC-902P) 0.05g / L
Additive fine particles: Si fine particles (Purity: 99.8%, average particle size 0.8μm)
Addition amount of fine particles: Change in the range of 25-50g / L Plating bath temperature: 35 ° C
Current density: 10 A / dm ^{2 to} 50 A / dm ²
Energizing time: 30 ~ 600sec
Stirring of the bath: Stirring so that the plate speed corresponds to 60 m / min. Electroplating was performed under the above conditions to form Fe plating in which Si fine particles were dispersed. The plating thickness was controlled by current density or energization time. The amount of fine particles dispersed was controlled by the amount added to the plating solution. The iron loss per kilogram (W _{1 / 10k} ) of the steel sheet after cooling was measured by the method shown in JIS-C2550 (2000). The results are shown in Table 1.

  As can be seen from Table 1, by forming the plating film according to the present invention, the iron loss is greatly reduced, and an electrical steel sheet exhibiting excellent electromagnetic properties can be produced.

(Example 2)
Using cold-rolled steel sheet with a thickness of 0.1 mm, which includes C: 0.003%, Si: 3.0%, Mn: 0.2%, Al: 1.2%, the balance being Fe and unavoidable impurities, After degreasing and pickling, Si fine particle dispersed Ni plating was applied to the surface of the cold-rolled steel sheet by electroplating under the following plating conditions.
<Plating conditions>
Anode: SS400
Bath composition: NiSO ₄ · 6H ₂ O 240g / L NiCl ₂ · 6H ₂ O 45g / LH ₃ BO ₃ 20g / L
(pH 3.0-4.5) Surfactant (Daiichi Pharmaceutical Co., Ltd .; Charol DC-902P) 0.05g / L
Additive metal fine particles: Si fine particles (purity: 99.8%, average particle size 0.8 μm)
Addition amount of fine particles: Change in the range of 25-50g / L Plating bath temperature: 35 ° C
Current density: 10 A / dm ^{2 to} 50 A / dm ²
Energizing time: 30 ~ 600sec
Stirring of the bath: Stirring so that the plate speed corresponds to 60 m / min. Electroplating was performed under the above conditions to form Ni plating in which Si fine particles were dispersed. The plating thickness was controlled by current density or energization time. The amount of fine particles dispersed was controlled by the amount added to the plating solution. The iron loss per kilogram (W _{1 / 10k} ) of the steel sheet after plating was measured by the method shown in JIS-C2550 (2000). The results are shown in Table 2.

  As can be seen from Table 2, by forming the plating film according to the present invention, the iron loss is greatly reduced, and an electrical steel sheet exhibiting excellent electromagnetic properties can be produced.

(Example 3)
Using cold-rolled steel sheet with a thickness of 0.1 mm, which includes C: 0.003%, Si: 3.0%, Mn: 0.2%, Al: 1.2%, the balance being Fe and unavoidable impurities, After degreasing and pickling, Si-48% Fe fine particle-dispersed Fe plating was applied to the surface of the cold-rolled steel sheet by electroplating under the following plating conditions.
<Plating conditions>
Anode: SS400
Bath composition: FeSO ₄・ 7H ₂ O 250g / L FeCl ₂・ 4H ₂ O 35g / L NH ₄ Cl 20g / L
(pH adjusted to 3.0-3.5) Surfactant (Daiichi Pharmaceutical Co., Ltd .; Charol DC-902P) 0.05g / L
Additive metal fine particles: Si-48% Fe fine particles (average particle size 3.4μm)
Addition amount of fine particles: Change in the range of 50-100g / L Plating bath temperature: 35 ° C
Current density: 10 A / dm ^{2 to} 50 A / dm ²
Energizing time: 30 ~ 600sec
Stirring of the bath: Stirring so that the plate speed corresponds to 60 m / min Electroplating was performed under the above conditions to form Fe plating in which Si-48% Fe fine particles were dispersed. The plating thickness was controlled by current density or energization time. The amount of fine particles dispersed was controlled by the amount added to the plating solution. The iron loss per kilogram (W _{1 / 10k} ) of the steel sheet after plating was measured by the method shown in JIS-C2550 (2000). No. 54 to No. 57 were then heat-treated at 1200 ° C. for 1 hour in an N ₂ -10% H ₂ atmosphere. The results are shown in Table 3.

  As can be seen from Table 3, by forming the plating film according to the present invention, the iron loss is greatly reduced, and an electrical steel sheet exhibiting excellent electromagnetic properties can be produced.

(Example 4)
Using cold-rolled steel sheet with a thickness of 0.1 mm, which includes C: 0.003%, Si: 3.0%, Mn: 0.2%, Al: 1.2%, the balance being Fe and unavoidable impurities, After degreasing and pickling, Si-40% Al fine particle dispersed Ni-20% Fe plating was applied to the surface of the cold-rolled steel sheet by electroplating under the following plating conditions.
<Plating conditions>
Anode: SS400
Bath composition: FeSO ₄・ 7H ₂ O 18g / L NiCl ₂・ 6H ₂ O 20g / L NiSO ₄・ 7H ₂ O 320g / L
(Adjust pH to 2.8-3.0) Surfactant (Daiichi Pharmaceutical Co., Ltd .; Charol DC-902P) 0.05g / L
Additive fine particles: Si-40% Al alloy fine particles (average particle size 3.4μm)
Addition amount of fine particles: Change in the range of 50-100g / L Plating bath temperature: 35 ° C
Current density: 10 A / dm ^{2 to} 50 A / dm ²
Energizing time: 30 ~ 600sec
Stirring of the bath: Stirring so that the plate speed corresponds to 60 m / min Electroplating was performed under the above conditions to form Ni-20% Fe plating in which Si-40% Al fine particles were dispersed. The plating thickness was controlled by current density or energization time. The amount of fine particles dispersed was controlled by the amount added to the plating solution. The iron loss per kilogram (W _{1 / 10k} ) of the steel sheet after plating was measured by the method shown in JIS-C2550 (2000). No. 72 to No. 75 were then heat-treated at 1200 ° C. for 1 hour in an N ₂ -10% H ₂ atmosphere. The results are shown in Table 4.

  As can be seen from Table 4, by forming the plating film according to the present invention, the iron loss is greatly reduced, and an electrical steel sheet exhibiting excellent electromagnetic properties can be produced.

(Example 5)
Using cold-rolled steel sheet with a thickness of 0.1 mm, which includes C: 0.003%, Si: 3.0%, Mn: 0.2%, Al: 1.2%, the balance being Fe and unavoidable impurities, After degreasing and pickling, Si-40% Al fine particle dispersed Fe plating was applied to the surface of the cold-rolled steel sheet by electroplating under the following plating conditions.
<Plating conditions>
Anode: SS400
Bath composition: FeSO ₄・ 7H ₂ O 18g / L NiCl ₂・ 6H ₂ O 20g / L NiSO ₄・ 7H ₂ O 320g / L
(Adjust pH to 2.8-3.0) Surfactant (Daiichi Pharmaceutical Co., Ltd .; Charol DC-902P) 0.05g / L
Additive fine particles: Si-33% Al-17% Mn alloy fine particles (average particle size 3.4μm)
Addition amount of fine particles: Change in the range of 50-100g / L Plating bath temperature: 35 ° C, current density: 50A / dm ^2, energization time: 170sec
Stirring of bath: Stirring so that the plate speed corresponds to 60 m / min. Electroplating was performed under the above conditions to form Ni-20% Fe plating in which Si-33% Al-17% Mn fine particles were dispersed. The amount of fine particles dispersed was controlled by the amount added to the plating solution. The iron loss per kilogram (W _{1 / 10k} ) of the steel sheet after plating was measured by the method shown in JIS-C2550 (2000). The results are shown in Table 5.

  As can be seen from Table 5, by forming the plating film according to the present invention, the iron loss is greatly reduced, and an electrical steel sheet exhibiting excellent electromagnetic properties can be produced.

Claims (7)

An aqueous solution containing at least one of Fe ²⁺ , Ni ²⁺ , and Co ²⁺ ions contains only one or more of Fe, Al, and Mn as selective elements in addition to Si and Si and inevitable impurities. Using a plating bath in which fine particles are suspended, an iron-based plating layer in which the Si fine particles are dispersed is formed by electroplating on at least a part of the surface of the metal material. surface, a surface treated metal material having a Si-containing iron-based plating layer, the front surface-treated metal material you wherein the Si content of the plating layer is not more than 3.5 mass percent 10 wt%. 2. The surface-treated metal material according to claim 1, wherein the surface-treated metal material is subjected to a heat diffusion treatment at a temperature of 1000 ° C. or more and 1200 ° C. or less after the electroplating. The plating layer is, in mass%, Al: 2.0 percent 8.0% or less, Mn: front surface treated metal material according to claim 1 or 2, characterized in that it comprises at least one than 0.5% 1.5% or less of . The thickness of the plated layer, the front surface treated metal material according to any one of claims 1 to 3 is 1μm or more 100μm or less. The composition of the metal material is mass%, C: 0.001% or more and 0.010% or less, Si: 0.01% or more and 3.5% or less, Mn: 1.5% or less, Al: 0.001% or more and 3.0% or less, and the balance is Fe and front surface treated metal material according to claim 1, which is unavoidable impurities. Using a plating bath in which fine particles mainly containing Si are suspended in an aqueous solution containing at least one of Fe ²⁺ , Ni ²⁺ , and Co ²⁺ ions, at least a part of the surface of the metal material is used. An iron-based plating layer in which Si fine particles are dispersed is formed by electroplating, and the fine particles mainly containing Si contain only one or more of Fe, Al, and Mn as selective elements in addition to Si and inevitable impurities. front surface processing method for producing a metal material you characterized in that it is. Wherein after electroplating, the front surface processing method for producing a metal material according to claim 6 for heating diffusion treatment at 1000 ° C. or higher 1200 ° C. or lower.